I NEVER took my bc at the same time. Neverrrrrr got pregnant once in 7 years. The reason they want you to take it at the same time each day is so there is a constant level of hormone in your body all the time w/ no fluctuations. If you're and hr or two late in taking it. You're VERY unlikely to get pregnant. That being said, perhaps setting an alarm on your cell phone will help you remember... for example set it for noon everyday and take it right when the alarm goes off. That's what i used to do
I would say your chances are about zero, but is there a reason you're not taking it at the same time every day?
I also havent use my birth control properly. I take it not as the same time every day.